#background-container {  
    position: fixed;  
    top: 0;  
    left: 0;  
    width: 100%;  
    height: 100%;  
    background-size: cover;  
    z-index: -1;  
}
#image11 {  
    width: 210px;  
    height: 280px;  
    position: absolute;  
    top: 120px;  
    left: 50px;  
}
#image12 {  
    width: 210px;  
    height: 280px;  
    position: absolute;  
    top: 120px;  
    left: 300px;  
}
#image13 {  
    width: 210px;  
    height: 280px;  
    position: absolute;  
    top: 120px;  
    left: 550px;  
}
#image14 {  
    width: 210px;  
    height: 280px;  
    position: absolute;  
    top: 120px;  
    left: 800px;  
}
.button-style {    
    display: inline-block;    
    padding: 10px 20px;    
    background-color: #4CAF50;  
    border: none;    
    color: white;    
    text-align: center;    
    text-decoration: none;     
    font-size: 16px;    
    margin: 4px 2px;    
    cursor: pointer;    
} 